diff --git a/charts/countly/values.schema.json b/charts/countly/values.schema.json
index a959976..5d2595e 100644
--- a/charts/countly/values.schema.json
+++ b/charts/countly/values.schema.json
@@ -101,8 +101,18 @@
             "string",
             "null"
           ],
-          "pattern": "^sha256:[a-f0-9]{64}$",
-          "description": "Image digest (takes precedence over tag when set)"
+          "anyOf": [
+            {
+              "pattern": "^sha256:[a-f0-9]{64}$"
+            },
+            {
+              "const": ""
+            },
+            {
+              "type": "null"
+            }
+          ],
+          "description": "Image digest (takes precedence over tag when set). Leave empty or null to use the tag."
         },
         "tag": {
           "type": "string",